Assigned Requests and Unassigned Requests

When a request first comes in from
an HTTP client to the load balancer, it is a request for a new session. A request
for a new session is called an unassigned request. The load balancer
routes this request to an application server instance in the cluster according to
a round-robin algorithm.

Once a session is created on an application server instance, the load balancer
routes all subsequent requests for this session only to that particular instance.
A request for an existing session is called an assigned or a
sticky request.